Extruding apparatus



1940- J. 5. BOYLE 7 2,185,701

I I EXTRUDING APPARATUS Filed Jan. 23, 1957 INVENTOR. Jams;- JBO YLE.

ATTORNEYS layer of the plastic material. It is desirable that v The housing or extruding head is preferably of a Patented Jan. 2, 1940."

, 2,185,701 EXTRUDING APPARATUS 1 J James S'. Boyle, Marion, Incl, assignor to Ana- Heo'nda" Wire & Cable Company, New York, I N. Y., acorporationof Delaware I Applicationr-January'23, 1937, Serial No. 121,970

' 2 Claims. (01. 13-13) 1 'My invention relatesgto. apparatus for extruding plastic materials as, for example, extruding. a sheathing of vul-canizablerubber about a c'n-.

.ductor.

'In extruding a plastic materialabout a central wire or conductor, the wire is drawn through a 'die through which is also forced an annular the conductor be centered exactly inthe center of the dieso' that the space between the conductor and the walls of-the die will .be equal throughout the circumference andthus result in a sheath of uniform thickness. For this purpose the wire or conductor is guided in and through a wire guide spaced from the extruding die so as to leave a passagefor the plastic'material.

Heretcfore the "extruding die andthe wire guide have been mounted independently in the housing or body of the extruding head. This arrangement frequently afforded an opportunity for the guide and wire to become off center which, for example, may be caused by a warp of the head or housing, or by other causes.

In my present invention I provide apparatus in which accurate centering of the .wire guide relative to the extruding die is ensured to provide a uniform coating of the extruded plastic.

The various features of my invention are illustrated by way of example in the accompanying drawing, in which I Fig. l is a longitudinal section through an extruding head embodying a preferred form of the invention. v

Fig. 2 is a front elevation of the head shown in Fig. 1. I s

Fig. 3 is a vertical section .tak'env on the line 3--3 of Fig. 1. f v Fig. is alongitudinal section ofa die sleeve forming a part of the extruding apparatus shown in Fig. l.

Fig. 5 is a longitudinal-section on a larger scale of parts of the apparatus at the'extruding die.

'In my invention I provide a die and guide sleeve which may be removed from the'housing or tubing head and which is accurately ma chined to position both an extruding die and a guidespindle in co-axial but longitudinally displaced position. This die sleeve ismounted in the housing or extruding head and is held in place therein between a pair of adjustable nuts.

T-shape having a side inlet for the plastic material, and thedie sleeve is, cut out ina part of its circumference for the passage-of the plastic material into the die Within the sleeve. The die and wire guide spindle are vremovably mounted in the die sleeve. v 1 Referring more particularlyto the accompanying drawing, theinvention is illustrated as applied to-an extruding head or housing l0 having a main bore to receive a die sleeve H and having a side inlet projection l2 through which plastic material may be forced. The housing is also provided with an overflow opening I2 throughfwhich excess plastic may flow under the control of a pressure release valve, not

- shown. The-die sleeve l l is mounted in the main bore of theextruding head and is held in position by an adjusting, nut I3 threaded into the outlet end of the head. By threading the nut, inwardly, the die sleeve may be adjusted longi: tudinally, being held against the nut l3 by the pressure of the plastic material forced into the head. The nut I3 may be held in any position of adjustment by' means of ,a screw [4 threaded into a screw hole in the front face of the extruding head and fitting into one of a series of. circumferential notches l5 in the nut. The in-- ner surface of the die sleeve at'the outlet end is tapered inwardly as at l6 tcward'a cylindrical 18 has a surfacetapered to form a continuation of the surface it and connecting in an outlet orifice at 2!. The die sleeve is cut away at 22 to leave a passage from the inlet tube l2 into the interior of the sleeve and thence to the die. The die sleeve II is prevented from turning by means of a longitudinal groove 23 which receives the end of a screw 24.

' In the end of the die sleeve ll opposite the outlet endthere is mounted a wire guide spindle 25 having an end flange 26. engaged between a shoulder 21 on the head l0 and a clamping nut 28. The nut 28 is provided with a central opening 29 through which a wire may enter into a passage 30 in the wire guide spindle. The spindle 25 is accurately positioned 45 I The flange 2B is dinal passage 33 for the Wire to be guided which is contracted as at 3 3 to the exact outer dimension of the wire.

From the above it will be apparent that the die and the wire guide may be accurately posithe Wire, and die is provided, thereby lessening or eliminating the risk of an uneven extrusion or thickness of the plastic material.

What I claim is:

1. Apparatus for extruding plastic material about a Wire which comprises a housing having a passage extending therethrough and open at itsopposite ends and an intermediate side opening thereinto, a die sleeve slidably mounted in said housing and having an extruding die at one end and tapered surfaces from said 'die'to the interior of said sleeve, an adjustable means on said housing to limit the position of said sleeve, a guide spindleslidably mounted in said sleeve, a Wire guide in said spindle and having a and spaced from the tapered surface of said-die,- the opposite end of said spindle having an outwardly extending flange, means for clamping said flange against a surface of said housing, said sleeve having. a side. passage. communicatin with the side passagez of'said housing.

2. Apparatus forextruding plastic material municating with said side opening; a die at one end of said sleeve, an adjustable stopj infsaid" housingto position the die end of said sleeve,

tapered outward surface centered relatively to, Y

10 about a wire which comprises a housing hav- "ing a cylindrical passage through which the;

.wire passesand a. side opening into said passage,

a sleeve in said passage having an opening cornsaid sleeveand die" having a tapered'inner opening, a guide Wire spindle slidably mounted in said 20 sleeve and having a Wire guide center-ed axially o'f"sai'd die, said spindle having an outwardly projecting flange and'said housing having 'a shoulder againstwhich said flange abuts and means for holding said flange tightly against. said shoulder. v

3 JAMES S. BOYLE." 

